Good morning. Welcome to "this week." Drone drama. Why was he killed? Let me finish. The president's reset in the war ror. This war like all wars must end. How will congress respond? Senator rand paul is here. Then -- I was just interested in putting it behind me. Retired general john allen speaks out for the first time since being cleared in the petraeus investigation. Plus, the irs scandal intensifies. I will not answer any questions. Or testify. And -- immigration reform inches forward. And in our "sunday spotlight," the creators of the hit show "homeland" join us. What will they reveal about season three. I spoiled a little bit already. Hello, again. George is off today. Great to have you with us. The president declared that we're at crossroads in the war on terror in a speech that both reset his national security policy and reignited some passionate debates. Including the issue on drone strikes. Our first guest, republican senator rand paul has been a key player in that debate since fili buster his controversy over drones back in the spotlight. On thursday, it sounded as if the president was responding directly to senator paul. I do not believe it would be constitutional for the government to target and kill any u.S. Citizith a drone or with a shotgun without due process, nor should any president deploy armed drones over u.S. Soil. Senator paul is with us now. Senator, thanks for joining us. Did the president address all of your concerns about drones? Well, I was pleased with his words and I was pleased that he did respond to this. However, there's still a question in my mind of what he thinks due process is. Due process to most of us is a court of law, it is a trial by jury, and, right now, their process is him looking at some flash cards and a powerpoint presentation on "terror tuesdays" in the white house. For a lot of us that's not really due process. One thing that the president did say there will be rules for the drone strikes. He said that targets pose a continuing imminent threat. Only near-certainty. No civilians hurt or killed. Not used to punish terrorists. That seems like a change? Yeah, but a lot of what's very important to myself and others is what the law says and how you should approach this. For example, it's not good enough to us that he's not using a power. We want him to assert that he won't -- that he doesn't have the power. For example, last year we passed legislation that I voted against, and that's detaining citizens indefinitely without a trial and sending them to guantanamo bay. The president said that he won't use that power. We think a president that believes in civil libertiliberties. I want to go back to the drone strikes for a moment. They also revealed this week for the first time publicly that four americans had been killed in drone attacks. Including al awlaki in yemen. Should he had not been targeted by a drone? My preference would be when an american commits treason if they're not actively involved in a battle -- if you're an american fighting with the taliban you're going to be shot with no due process. But how do you go after someone like awlaki? Let me finish my point. Let me finish my point, so we can have a discussion. But, if you're conspiring to attack america and you're a traitor, I would try you for treason if you don't come home for the trial I would try you in absentia. And the death penalty has been used throughout our history for treason. A judge looks at evidence and that's something that separates us from the rest of the world. We adjudicate things by taking it to an independent body that's not politically motivated. Or elected. The president did speak of closing guantanamo. No specifics, though. You think it should be closed? No, I think it's become a symbol of something, though, and I think things should change. For example, I think people being held there are bad people. What I do them, them, try them in military tribunals. I think that would go a long way in showing the world we're not going to hold them without charge forever. I want to move on to the irs. Do you believe that this was limited to the tea party, targeting the tea party, or do you believe there were other groups as well that were targeted? You know, I don't know. I don't know whether people were targeted for conservative religious values or just conservative political values. And sometimes there's an overlap. I think we have to get to the bottom of this. I think these three scandals really takes away from the president's moral authority to lead the nation. No one questions his legal authority. I think he's losing the moral authority to lead this nation. He really needs to put a stop to this. I don't care whether you're a democrat or republican, no one likes to see being punished for your political belief. You called for a special counsel? Do you see any evidence that a crime has been committed thus far? I don't think we know so far. The main woman from the irs that's involved has taken the fifth amendment. She's no longer cooperating. So, I have called for her suspension. The president has suspended her, but he's still paying her. I think there needs to be a resolution. I think the president is in danger of losing his moral authority to lead the nation. The president said that he's going to listen to his commissioner, his new irs commissioner in 30 days, the investigation has been going on for over a year. If he goes beyond 30 days and no one is fired over this, I really think it's going to be trouble for him trying to lead the next four years. Let's move to immigration. Would you support the bill, the senate bill that made it through committee this week? I support immigration reform. At this time, I think the bill needs to strengthen border security. It also needs to expand work visas. The main problem with illegal immigration is we don't have enough legal immigration. This bill actually lowers the numbers for work visas, that's exactly the wrong direction to go. So, I will support a bill that fixes it. And I do want to support a bill. I talked to the authors of it. If they'll work with me on the amendment there's a very good chance that I could vote for it. But it has to be a better bill. And a pathway to citizenship? I would say no, new pathway. I'm little concerned that some will interpret and there will be a new pathway. Because they created a new visa category. My preference would be to change the law that says you can't simultaneously be in the work visa line and the pathway to come to this country. As long as somebody who has a work visa is treated the same as a new person in mexico city who wants to get in line tomorrow, i don't have a problem getting in the normal line. I just don't want to create a new line or give a new preference to people who are here undocumented. But I'm all in favor of allowing undocumented workers becoming documented workers. Thank you for joining us, senator paul.

This transcript has been automatically generated and may not be 100% accurate.

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